You could be taking up more than 10 GB, yes. I believe that when you say DROP TABLE, the actual deallocation is deferred to the Ghost Cleanup process that runs as a background task. So if you load the table anew before you the clean has completed, you may not be able to reuse the pages from the old table.
I will need to confess that I am not 100% confident on this answer. I think that if you really want to know, you would need to test.